This invention relates to clutch disks adapted for use in dry friction clutches. More particularly, the invention relates to means for securing friction elements to such disks.
In certain heavy duty clutch designs, there is a need to accommodate lateral deflection of friction elements which occurs during transition between clutch disengagement and full clutch engagement, referred to herein as "transitional" clutch engagement. In heavy duty clutch systems, the greatest amount of lateral deflection occurs during the transitional engagement phase.
In most prior art clutch systems, lateral deflection is typically accommodated by cushioning the spacing between friction elements positioned on opposed or opposite sides of the clutch disk. This is accomplished by adding spaces, springs, or both between opposed friction elements. Such systems, however, do not address the problem of stress in the rigid connections between the friction elements and disks. Most systems will employ spot welding for the connection, or will utilize rivets for this purpose. The stress loads on the spot welds or rivets are relatively high, causing frequent cracking within the otherwise normal useful life of the clutch. Ideally, rigid connectors are avoided at locations of high stress, such as at the interface between friction element assemblies and the clutch disks to which such assemblies are secured.